Store and retrieve NSAttributedString or NSMutableAttributedString

gistfile1.txt

    NSMutableAttributedString *string = [[NSMutableAttributedString alloc] initWithString:@"Hello, world!"];
    [string addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(0, 3)];
    [string addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:24] range:NSMakeRange(3, 3)];
    
    NSData *data = [string dataFromRange:NSMakeRange(0, string.length) 
                            documentAttributes:@{NSDocumentTypeDocumentAttribute: NSRTFDTextDocumentType, 
                            NSCharacterEncodingDocumentAttribute: [NSNumber numberWithInt:NSUTF8StringEncoding]} 
                            error:nil];
    
    
    NSAttributedString *string2 = [[NSAttributedString alloc] initWithData:data 
                                                              options:@{NSDocumentTypeDocumentAttribute: NSRTFDTextDocumentType, 
                                                              NSCharacterEncodingDocumentAttribute: [NSNumber numberWithInt:NSUTF8StringEncoding]} 
                                                              documentAttributes:nil 
                                                              error:nil];